The present invention relates to a linear slide bearing suitable for use in various sliding parts such as the table saddle of a machine tool, the slider of a machining center and the slider of a transportation robot for reciprocative transportation of a heavy object.
Generally, a conventional linear slide bearing incorporates bearing races as essential parts thereof. This bearing race, usually made of a flat plate member, is liable to be distorted and twisted when it bears a load, resulting in an unsmoothed recirculation of balls running along the bearing race, due to variation of contact pressure between the ball and the bearing race along the length of the bearing race. The bearing race is usually fixed by means of screws. Therefore, a troublesome work is required to fix the bearing race by the screws, particularly when the bearing race has to be fixed at many points. The fixing of the bearing race by means of screws is disadvantageous in that quite a delicate adjustment of screw tightening force is required in order to correctly locate and mount the bearing race.
Another problem encountered by the conventional linear slide bearing arises from the difficulty in the formation of non-loaded ball grooves in the main body of the bearing. In the production of the conventional linear slide bearings, the non-loaded ball grooves are formed in the main body of the bearing by drilling. It is extremely difficult to form the non-loaded ball grooves in the aimed portions of the main body of the bearing directly by drilling. This difficulty not only impairs the precision of machining but also raises the production cost due to a too long time required for the drilling.